Apparatus for arresting launching devices for airplanes



R. H. FLEET Er AL. 2.210.449

APPARATUS FOR ARRESTING LAUNCHING DEVICES FOR AIRPLANES Aug. 6, 1940.

Original Filed Nov. 25, 1936 ZSheets-Sl meet 1 A 5 R. H. FLEET E'ZT-AL I 2,210,449-

I 'APPARATUS FdR ARRESTING LAUNCHING DEVICES FOR AIRIPLANES Y Original Filed Nov. 25, 1936 2 shee ts sheet 2 r 11/ 1 v I I Patented Aug. 6, 1940 APPARATUS FOR ARRESTING LAUNonmG DEVICES FOR AIRPLANES Reuben H. Fleet, William B. Wheatley, and Isaac M. Laddon, San Diego, Calif.

Original application November 25, 1936, Serial No. 112,803. Divided and this application June 22, 1937, Serial No. 149,782

9 Claims.

Our invention relates to launching means for airplanes either of the sea or land type.

This is a division of our co-pending application Serial No. 112,803, filed November 25, 1936. In the application above referred to the construction and operation of the system is set forth at length, together with the advantages of this type of system. It is thought unnecessary here to repeat in detail the discussion in that applil0 cation. This application is directed to a construction for increasing the safety factors in launching an airplane from a movingvehicle.

Not only are the brakes automatically applied when the airplane leaves the vehicle, but a sup-' plemental braking is effected by means of arresting gear cables. I

Further, the braking of the vehicle is under the control of the pilot in theplane. This control of the braking feature is of great importance since if anythinggoes wrong, or if flying speed is not attained in aperniissible length of run the pilot can remain on the vehicle and apply the brakes himself to the vehicle.

Airplanes as-used herein broadly includes land airplanes, seaplanes, flying boats, airboats, am-

phibians and any -other heavier-than-air-aircraft. Body element and body unit as used herein broadly includes a land airplane fuselage, a flying boat airboat or amphibian hull, and the equivalent of a body in the case of a flying wing airplane having no external body.

It is an object of our invention to provide positive means for braking a vehicle supporting 'an airplane for launching which is powerful in effect,

sturdy in constructionand easy to repair and replace.

Another object of our invention is to provide a construction which will permit the pilot to apply the brakes on the vehicle on which the airplane rests for launching.

A further object of the invention is to provide such a construction which is positive in operation and simple in construction.

. With these and other objects in view, which may be incident to our improvements, the invention consists in the parts and combinations to be hereinafter set forth and claimed, with thev understanding that the several necessary elements comprising our invention may be varied in construction, proportions and arrangement, withoutdeparting from the spirit and scope of the appended claims.

In order to make our invention more clearly understood, we have shown in the accompanying drawings means for carrying the same into practical effect without limiting the improvements in their useful applications to the particular constructions, which for'the purpose of explanation, have been made the subject of illustration.

In the drawings:

Figure 1 is a view in side elevation with parts broken away, showing a seaplane mounted on our launching vehicle on rails, the general disposition of the braking system and the controls 10 being shown;

Fig. 2 is a detail view in perspective showing the construction of our'braking linkages;

Fig. 3 is a perspective view in detail of the compressed air storage tank, piping connectionsand valve;

Fig. 4 is an exploded view partly in section taken through our valve and valve control mechanisms;

' Fig. 5 is a view taken along the line 55 of 5 Figure 4, lookingin the direction of the arrows;

Fig.- 6 is a view taken along the line 66 of Figure 4, looking in the direction of the arrows;

Fig. '7 is a view taken along the line'-'|-1 of Figure 4', looking in the direction of the arrows. 5

Referring to the drawings we have shown a seaplane l which is mounted on a cradle 2 that is pivoted at 3 on supports 4 carried on top of a car 5. The car 5 is'mounted on wheels 6 which rest on rails 1. At the end of the track I is 30 diagrammatically illustrated at 8 an arresting gear cable,

The details of the arresting gear cable and the mechanism for keeping the cable taut are not shown as these are Well known. The arresting 35 gear cable is adapted to be caught in arresting gear catch elements 9 mounted at either end of the car 5. These elements 9 are provided with throats Ill in'which the cable is adapted to be engaged, and pivoted latch members II which 40 are raised when the cable enters the throat Ill, and fall in place behind the cable after the cable is at the bottom of the throat 10. These arresting gear cables which are at the ends of each track of the'system provide a' safety measure in 5 case the brakes have not fully brought the car to rest.. The braking system will be described later. The car 5 is provided with a top I! and sheathing 13 which comes partially over the wheels 6 and cuts down the wind resistance. The 50 car at each end, as indicated at I4, is streamlined to reduce air resistance.

The brakes for the front and rear trucks of the car are of the pneumatic type. The system at either end of the. car is the same. Compressed air is stored in a tank I5 mounted on the cradle 2 and held to the upper part of the cradle 2 by means of brackets I6. Attached to the compressed air tank is a compressed air line I! having a branch line I8 with a pressure gauge I9 mounted therein. At the end of the branch line I8 is a one-way valve 20 which is adapted to be connected with some suitable source of compressed air near the air port. There is a cutoff valve 2| provided in the line IT. The tank I5 is filled through the valve 20 to the proper pressure, as indicated by the pressure gauge I9.

The line I! leads to a valve construction 22 from which there is an air outlet line 23 of flexible construction, such as rubber, which is connected by means of a T-fltting 24 to a pressure line 25 which runs to the trucks at either end of the car 5.

At either end of the car 5 are located braking cylinders 26 which are connected by flexible hose 21 to the line 25. The braking cylinder construction is not shown in detail, and comprises a cylinder with a piston (not shown) connected to a' piston rod 28 which carries a bifurcated end element 29 which is pivoted at 30 to an equalizing bar 3| oi the braking system. It is to be understood that the system is the same for each end of the car.

The equalizing bar 3| is pivoted to links 32 which are pivoted to arms 33 that are mounted for rotation in supports 34 suitably supported by the framework of the truck which carries the wheels 6. Connected to the arms 33 are arms 35 which are pivoted at 36 to links 31.

The links 31 are pivoted at 36 to one end of bell crank levers 39. The center of the bell crank levers is pivoted at 40 to the top of brake shoes The other arm of the bell crank levers is pivoted at 42 to links 43 which are pivoted at 44 to links 45. The links 45 are pivoted at 46 to the 'top of the other brake shoes c1 of the system.

The tops of the links 45 are pivoted to support bars 48 carried by the trucks. Also links 40 are provided for supporting the brake shoes 4I, the links being suspended from support pivots 50.

Upon admission of air through the flexible line 21 the equalizing bars 3| are pushed by the piston (not shown) in the cylinders 26 in a direction to rotate the arms 33 to cause the arms 35 to press against the upper arms of the bell crank levers 39, thus swinging the brake shoes 4| into contact with the surface of the wheels 6.

Through the lower arms of the bell crank levers 39 and through linkage 45, brake shoes 41 are also applied to press against 7 their respective wheels 6. In this manner braking is efiected both on the front and the rear trucks oi the car 5.

Upon release of pressure in the line 25 the brakes are released. In this type of construction there is usually a spring in the cylinder 26 which returns the parts to their starting position. Return springs can be used at other locatlons than in the cylinder 25.

We will now describe the valve mechanism and the valve control.

Referring to Figure 3, and particularly to Figur'es 4 to 7 inclusive, we have shown the valve casing 22 as comprising a central cylindrical aperture 5| in which is adapted to rotate a valve disk 52 provided with holes 58 and flfiiffirtion of the valve disk 52 is cut away, as indicated at 55, and a limiting stop 56 mounted on the inner wall of the aperture 5I is adapted to 111; into the slot to limit the rotative movement of the valve ineither direction.

with the parts or the valve in the position shown in Figure 7, the hole 54 communicates with an exhaust exit 51 formed in the valve casing. The line 23 to the brake cylinders communicates with a fitting 58 which in turn communicates with an aperture 59 which lies directly below the aperture 53 formed in the rotative disk 52. In this position of the parts air under pressure flows back from the brake cylinders 26 through the valve, intothe aperture 5| of the valve and out through hole 54 in the disk 52 and through exhaust 51.

When the valve is rotated so that the stop 56 lies against the other extremity of the slot 55, the hole 54 lies directly over aperture 59 leading to the line 23 to the brake cylinders, and hole 53 lies directly above an inlet aperture 60 formed in the valve casing 2 I, to which is connected through a coupling 6| the air inlet pipe II. From the air inlet pipe I! compressed air flows through aperture 50, through aperture 53 in the, valve disk 52, and through aperture 54 in the valve disk 52 into an aperture 59, and compressed air is thus introduced through the line 23 into'line 25 which sends compressed air to each of the brake cylinders 26. Our. mechanism is so constructed that the rotation of the valve just described can be effected either under control of the pilot, or when the airplane leaves the cradle 2 and takes to the air. It is to be noted that in the position of the parts shown in Figure 1, the cradle 2 is resting on a forward support 62. In this position of the parts the airplane is in the no-lift attitude which permits the airplane and the car to pick up speed more readily than in any other position. When flying speed is obtained, the pilot through the controls rotates the airplane on the cradle 2 so that the cradle 2 rests on the rear support 63 and the airplane takes oil. Provision is made.

when an airplane takes off, as will now be described, for the application of the brakes on the car. Likewise if the airplane does not take off and the pilot desires to stop the car and airplane, this can be effected.

The control mechanism comprises a Bowden wire I00 which is attached to a fixture "II which is bolted to, or integrally formed with, a connection I02 which rests on top and is keyed to, or integrally formed with, the valve disk 52. The mechanism just described is adapted to rotate in suitable fittings which we have indicated generally at I03. There is a sheathing provided, as indicated at I04, for the Bowden wire.

The top end of the Bowden wire is attached to a shank I05 which carries a pull o'ut member I06. The shank and pull out member are held in place on the Bowden Wire by suitable fittings, generally order to form a frictionless fit between the cylinder II I and the guide member IIO, we have provided for lubricating oil waste II5, which is held in place by means of a screw cap H6 mounted on the cylinder III.

The pull out member I06 is held in place in the de member II 0 by means of a ball II! which is pressed into an aperture IIB formed in the Pull out member I06. The ball is held pressed car he pulls the Bowden wire I2'I Figure 4. This causes into the aperture H8 by means of a compression spring H9 carried in an aperture I20 formed in the guide member I I0. The tension of the spring H9 is sumcient to enable a pull on the Bowden wire connection I00 to exert a considerable downward pull on the guide member H0. The spring pressure is regulated to enable this pull to effect the functions which will be later described.

The cylinder III is provided with a laterally extending fitting I2I having an aperture I22 which carries a compression spring I23 which abuts at one end against a helically toothed rack I24 which meshes with the helical teeth on the pinion II2.

The rack I24 carries an extension I25 over which the spring I23 fits. The extension I25 is reduced in diameter at its end I26, as illustrated in Figure 4, and this reduced end is attached to another Bowden wire I21 adapted to slide in a sheathing I28 which is mounted on a suitable fixture indicated generally by the numeral I29 at the end of the laterally extending fitting I2I. The helical pinion H2 is provided with an upwardly extending stem I30 to which is secured a cap I3I. To tension the helical pinion I I2 in the up position, we have provided a compression spring I32 which bears at one end against the cap I3I and at the other end against the top I33 of the control fitting.

The spring I32 is not as strong as spring I23, for a purpose which will now be described.

If the pilot wishes to apply, the brakes on the in the direction of the arrows shown in the rack I24 ,to rotate the helically toothed pinion II2 which turns the guide member H0 and rotates the pull out member I06. This causes the Bowden wire I00 to rotate the valve disk 52 to cause it to assume a positiozito admit compressed air to the brake cylinders. Upon release of tension on the Bowden wire I2'I the spring I23 will push the rack back again into the position shown in Figure '4, which causes the valve parts to assume the position shown in Figure 'I and allows the air to exhaust from the brake cylinder Let us assume that the seaplane I is taking off from the cradle and that tension is exerted on the Bowden wire I00. member I05 which, because of the position of the ball III in the aperture II8, causes the pull out member I06 to pull down strongly on the guide member H0, and the guide member is .pulled downwardly carrying with it helical gear II2. By reason of the fact that the helical gear H2 is in mesh with the helical gears of the rack I24, the gear II2 will be rotated, since thespring I23 is strong and tends to hold the raclr'in the position shown in Figure. 4. This rotation of the gear H2 is transmitted through guide mem-. ber IIO, through pull out member I06 to Bowden wire I00, and thence to the valve disk 52. The valve disk is rotated into a position to admit air to the brake cylinders. Thus the car 5 is arrested. The pull out member I06 is pulled out from its position in the guide member IIO very shortly after the valve-disk 52 has been rotated and thus there is nothing to rotate the valve disk 52 back into the ofi position, since there is no longer contact between the pull out member I06 and the guide member IIO.

From the above it is apparent that the pilot can apply the brakes at will to the vehicle upon which the plane is being transported for launching. Moreover an automatic means for applying This pulls on pull out the brakes upon the airplane leaving the vehicle has been provided.

This mechanism just described introduces an added safeguard in the take-off of an airplane from a launching vehicle since if sufficient speed has not been acquired, or something in the way of other emergency occurs, the pilot can apply the brakes on the vehicle and not take off. Moreover, the vehicle will be stopped by the braking system on the vehicle after the airplane has left the cradle. In both instances the operation of the brakes on the vehicle is supplemented by the additional safety factor furnished by the action of the arresting gear cable.

The center of gravity of the airplane is about one quarter chord distance from the leading edge of the wing in most cases. In the present drawings the airplane is shown a little to the rear of the preferred position in'the cradle. It is desirable that the center of gravity of the airplane in the cradle be a little forward of the cradle pivot so that the airplane will easily remain in the position indicated in Figure 1, with the cradle contacting the forward support.

While we have shown and described the preferred form of our invention, we wish it to be understood that we do not conflne ourselves to the precise details of construction herein set forth by way of illustration, as it is apparent that many changes and variations may be made therein, by those skilled in the art without departing. from the spirit of the invention, or exceeding the scope of the appended claims.

, "'We'claim:

1'.- A control mechanism comprising a rotary valve for controlling the flow of a fluid, anchor means, a rotation transmitting link between the anchor means and the valve, a helical rack carried by the anchor means, a helical pinion carried by the anchormeans, and means to move the pinion laterally on the rack to rotate it as the anchor means moves away from the valve.

2. Acon'trol mechanism comprising a rotary valve for controlling the flow of a fluid, anchor means, a rotation transmitting link between the anchor means and the valve, a helical rack carried by the anchor means, a helical pinion carried by the anchor means, means to move the pinion laterally on the rack to rotate it when the anchor means leaves the valve, and a pull out device for the link permitting such relative movement .of valve and anchor means.

3. A rotary mechanism comprising a rotary valve for controlling the flow of a fluid, anchor means, a rotation transmitting link between the anchor means andthe valve, a helical rack carried by the anchor means, a helical pinion carried by the anchor means, means laterally on the rack and rotate it when the anchor means leaves the valve, and a Bowden wire connection operable from a remote location to rotate the rotation transmitting link.

4. A control mechanism comprising a rotary valve for controlling the flow of a fluid, anchor means, a rotation transmitting link between the I anchor means and the valve, a helical rack carthe anchor means, a helical-pinion carried ried by by the anchor means, means to move 'the pinion laterally on the rack to rotate it when the anchor means leaves the valve, and means to control the movement of the valve when the anchor means and the valve remain in the fixed position relative to each other. I

valve for controlling the flow of a fluid. anchor to move the pinion 5. A control mechanism comprising a rotary leaves the valve, and means to cob means, a rotation transmitting link between the anchor means and thevalve, a helical rack carried by the anchor means, a helical pinion carried by the anchor means, means to move the pinion laterally on the rack to rotate it when the anchor means leaves the valve, a pull out device for the link permitting such relative movement of valve and anchor means, and means to control the movement of the 'valve when the anchor means and the valve remain in the fixed position relative to each other.

6. A control mechanism comprising a rotary valve for controlling the fiow of a fluid, anchor means, a rotation transmitting link between the anchor means and the valve, said rotation transmitting link including a Bowden wire connection, a helical rack carried by the anchor means, a helical pinion carried by the anchor means,

means to move the pinion laterally on the rack.

to rotate it when the anchor means leaves the valve, a pull-out device for the link permitting such relative movement of the valve and anchor means, and means to control the movement of the valve when the anchor means and valve remain in the fixed position relative to each other.

7. A control mechanism comprising a rotary valve for controlling the fiow of a fluid, anchor means, a rotation transmitting link between the anchor means and the valve, said link including a'Bowden wire connection, a helicalrack carried by the anchor means, a helical pinion carried by the anchor means, said Bowden wire connection.being adapted to move the pinion laterally on the rack to rotate it when the 'nchor means l the movement of the valve when the anchor means and the valve remain in the fixed position relative to each other.

8. A controlmechanism comprising a frame member, a rotatable member axially sliding therein, means to limit the extent of said axial slid ing, said rotatable member having a gear portion with helical grooves thereon, a rack member carried by the frame member and adapted to engage said helical grooves with complementary grooves, said frame member positioning the rack member for remaining in continuous engagement with said gear during the movement of said gear, an engaging member resistably interfltting with the rotatable member, valve means connected to the engaging member, whereby the valve means is rotated when the frame member leaves the valve means.

9. A control mechanism comprising a frame member, a rotatable member axially sliding therein, said rotatable member being springurged toward its innermost position, said rotatable member having a gear portionwith helical grooves thereon, a rack member adapted to engage said helical grooves with complementary grooves, said frame member positioning the rack member and gear for sliding in continuous engagement with each other, an engaging member resistably interfitting with the rotatable member, valve means connected to the engaging member whereby the valve is rotated when the frame member leaves the valve means and the rotatable member is pulled away from its innermost position, control means for sliding the rack member, whereby the valve means may be rotated without the frame member leaving the valve means.

REUBEN H. FLEET. WIILIAM B. WHEA'I'LEY. ISAAC M. LADDON. 

